1. Field of the Invention
The invention relates to the systems, devices and methods used to transmit messages over a data network and, more particularly, to systems, devices, and methods that transmit Aircraft Communications Addressing and Reporting System (ACARS) text messages over Ethernet or Avionics Full Duplex (AFDX) data buses.
2. Description of the Related Art
Traditionally, the ARINC 619 protocol, designed specifically for exchange of datalink messages over ARINC 429 point-to-point data busses has been used to transmit and receive ACARS messages. ARINC 619 provides an industry standard specification for formatting of routing information and how it is included it with the data to be exchanged.
The ARINC 429 standard was developed by the aviation industry as a standard communication protocol. Prior art avionics systems used point-to-point (ARINC 429) data buses for communication. As ARINC 429 systems developed the Williamsburg file transfer protocols, defined in ARINC 429P3-18, were developed to transfer files larger than 32 bit words. Thus, in these latter systems, data was transferred using Williamsburg over ARINC 429. As ACARS systems developed the ARINC 619 protocol was developed to provide the required ACARS information. Thus, for ACARS systems, data was transferred using ARINC 619 over Williamsburg/ARINC 429.
In contrast, Ethernet data buses and associated communication protocols were developed by the computer industry to interconnect computers. Ethernet provides for higher data rates and accommodates larger file sizes. However, due to different development paths, Ethernet devices are not directly compatible with ARINC 429 devices. Similarly, network protocols used over Ethernet networks are not directly compatible with legacy devices transmitting and receiving ARINC 619 messages.
Consequently, as avionics system designs migrate from the traditional federated systems using point-to-point (ARINC 429) data buses to an Integrated Modular Avionics (IMA) using networked data buses, such as the Avionics Full Duplex (AFDX) data bus or Ethernet, the need arises to create a protocol to be used across all systems which would minimize the cost of changes to legacy equipment to enable it to use the new data bus architecture.